The present invention relates to a method for inclining a chair seat, by which the backrest side of a seat is upwardly inclined when being seated, and to a chair having an inclinable seat.
Conventionally, a method for inclining a chair seat and a chair having an inclinable seat, which are disclosed in U.S. Pat. No. 5,605,376 (Feb. 25, 1997) previously filed by the present applicant, have been known as an example of this kind of a chair seat.
This example is such that a backrest attaching member is pivotally supported so as to be inclined at one side of the attaching frame opened upward and consisting of a bottom plate and side plates and is pressed to the bottom plate side of the attaching frame, wherein a seat receiving plate is inclinably pivotally supported at the other side of the attaching frame so that the back attached to the backrest attaching member is caused to incline rearwardly. Thereby a push-up member existing at the tip end of the backrest attaching member causes the seat attached to the seat receiving plate to be upwardly inclined along with the seat receiving plate.
In conventional examples, since the attaching frame which is upwardly opened is used, in a case where attaching and tightening means such as bolts, nuts, screws, pins, etc. of components are loosened or come off, it is necessary that the seat is removed from the seat receiving plate and the seat receiving plate is further removed from the attaching frame, and thereafter the attaching and tightening means are tightened and fixed. That is, no maintenance can be carried out from the outside of the attaching frame, that is, as it is assembled. This would cause a problem in maintenance.
Furthermore, a taper bushing or a straight bushing is welded to the attaching frame and is fixed there for fixing the tip end of the supporting column of the chair leg to the attaching frame. That is, this fixing member can meet the leg of only one kind of chair. It is impossible to replace the fixing member attached and fixed at the attaching frame, and it is impossible to meet the legs of various kinds of chairs having parts and supporting column, the sizes of which are different from each other. This would cause another problem.